Electrophotographic imaging members may be in the form of plates, drums or flexible belts. These electrophotographic members are usually multilayered photoreceptors that include a substrate, a conductive layer, an optional hole blocking layer, an optional adhesive layer, a charge generating layer, and a charge transport layer, an optional overcoating layer and, in some belt embodiments, an anti-curl backing layer.
Due to differing electrical response requirements for different photoreceptors, companies have conventionally developed formulations for the charge generating layer using a variety of charge generating materials, binders, and solvents. The cost to develop new charge generating compositions using different sets of materials and the implementation of these new charge generating compositions into production increase the photoreceptor unit manufacturing cost. There is a need, which the present invention addresses, for a new photoreceptor fabrication method where a different electrical response requirement for a photoreceptor can be accommodated by adjusting one set of materials for the charge generating composition without losing the dispersion stability thereof. Thus, the present invention allows for a number of different charge coating compositions to be developed from one set of materials, thereby saving money in development costs and materials investment, as well as providing faster delivery of specific photoreceptors.
Photoreceptor coating compositions and methods for making them are disclosed in Cosgrove et al., U.S. Pat. No. 5,686,213; Nealey et al., U.S. Pat. No. 5,418,107; Stegbauer et al., U.S. Pat. No. 5,324,615; Nukada et al., U.S. Pat. No. 5,393,629; and Mayama et al., U.S. Pat. No. 5,418,099.
BUTVAR.RTM. resins are described in a five page brochure from Monsanto Chemical Company, the disclosure of which is totally incorporated herein by reference.
A Type V hydroxygallium phthalocyanine is described in Katsumi Daimon et al., "A New Polymorph of HydroxyGallium Phthalocyanine and its Application for Photoreceptor," Proceedings: IS&T's Tenth International Congress on Advances in Non-Impact Printing Technologies, pp. 215-219 (1994).